1. Technical Field
The present invention relates to the field of satellite multi-access control mechanisms and, more particularly, to apparatuses and techniques for controlling random access to satellite communication networks.
2. Description of Related Art
Various types of multiple access schemes are known to allow multiple users to utilize satellite communication system resources.
A substantial improvement to the basic ALOHA system is described in U.S. Pat. No. 5,053,782('782 patent) having a common assignee as the present application. Other variants of the ALOHA scheme include U.S. Pat. No. 5,084,900 ('900 Patent) and U.S. Pat. No. 5,138,631 ('631 patent) to Spacenet, a subsidiary of the present assignee.
Coordinating the data transfer from the hub to the VSATs (outbound) is relatively simple because the hub is a unique source of information. However, coordinating the data transfer from the VSATs to the hub (inbound) is significantly more complex particularly where there are thousands, tens of thousands, or even hundreds of thousands of terminals vying to access the same satellite resources in a non-synchronized manner. There is a need for a satellite network to connect a very large numbers of very small aperture terminals (VSATs) and one or more central stations (hubs) via a two directional communication satellite link. Current schemes are limited in their performance. In particular, the maximal utilization under a given response time constraint is limited. Thus, there is a need for a system and method for a multiple access scheme which allows a very large number of remote stations with infrequent bursts of data to communicate over a shared VSAT channel in a more efficient way than currently known multiple access schemes provide. Further, the system needs to be inexpensive so that it may deployed in a mass market bringing the benefits of VSAT technology to the average consumer.